How to Influence CO 2
How to Influence CO2 Contents Introduction.................................................................................................. 3 COP15 ”Hopenhagen”.................................................................................. 5 The Decision-making............................................................................... 5 The Copenhagen Accord.............................................................................. 5 The International Maritime Organisation (IMO)................................................ 6 Choice of Engine Power and rpm.................................................................. 7 Engine Efficiency........................................................................................... 9 Waste Heat Recovery System..................................................................... 10 Turbocharging Layout.................................................................................. 11 LNG and LPG as Fuel................................................................................. 12 Diesel Engines Burning Biological Oils and Fat............................................. 13 Green Ship of the Future............................................................................. 16 Carbon War Room...................................................................................... 16 Conclusion and Other Measures Discussed to Increase Efficiency................ 17 How to Influence CO2 Introduction measurements show that the world Talking about greenhouse gas, global The purpose of this paper is to turn average temperature is changing. CO2 warming and CO2, Fig. 1 shows the focus on CO2 emissions from marine absorbs and emits radiation within the results of produced CO2 which has an engine operation. The paper describes atmosphere, which then influences the impact on the CO2 level in the atmos- the attention from the world society, average temperature of the earth. Sci- phere. the regulation expected from interna- entists and politicians fear that this may tional organisations and how we can affect the climate in such a way that it Besides the naturally produced CO2, influence CO2 emission by means of will influence the way of living on earth the use of fossil fuels constitutes the engine optimisation, waste heat recov- drastically. This has caused politicians, other large contributor. Oil, coal and ery and alternative fuels. industries and organisations worldwide gas, which millions of years ago were to look for ways to decrease human- organic materials exposed to high pres- MAN Diesel & Turbo is convinced that caused CO2 emission to prevent this sure, consist primarily of carbon releas- CO2 emission will continue to be an im- from happening. ing energy when reacting with oxygen portant subject and, eventually, strict to create CO2 and water. regulations influencing the ship speed Naturally, produced greenhouse gas, and operation will be introduced. such as water vapour, is regarded Human-created CO2 and the natural the most influencing greenhouse gas CO2 balance will be lowered by reduc- As illustrated in the paper, a number of with a contribution of 36-72% to the ing the use of fossil fuels. design and application features can be greenhouse effect, and CO2 influenc- used to reduce CO2 emissions from the ing 9-26%. Exact figures are hard to 1. From the atmosphere to the oceans marine market. establish because some of the effect- Approx. 90 Gt/year of CO2 is ex- ing gasses absorb and emit radiation changed between the oceans and But what is CO2, and why all this sud- at the same frequency as others and, the atmosphere. There is a net ab- den fuss about CO2 and greenhouse therefore, are difficult to distinguish sorption in the oceans of approx. 2.2 gasses in general? The reason is that from each other. Gt/year. 2. From human activities to the atmosphere Burning of fossil fuels: peats, coal, 3 oil and gas. 7.2 Gt/year in total is emitted to the atmosphere. Some 1 scientists (from GEUS) believe that 2 the emission may be as high as 22 Gt/year, which means that the 6 2 carbon accumulation is far larger. 3. From the geosphere to the atmosphere Carbon is released from the sedimentary layers when heating transforms them to crystalline rock (e.g. 4 silicate rock types such as feldspar). 5 The carbon is released by volcanic activity. Approx. 0.1 Gt/year of CO2 is emitted to the atmosphere. Fig. 1: CO2 contributors MAN B&W Diesel How to Influence CO2 3 4. From the atmosphere to rivers and lakes (the hydrosphere) Carbon is drawn out the atmosphere of Boing 747 rock. The carbon ends in rivers and Heavy Truck by weathering/decomposition lakes or in the sea. A total of 0.2 Gt/ year is drawn from the atmosphere to the hydrosphere. Rail – Diesel Rail – Electric Container Vessel 5. From the biosphere to the geosphere 0 km The decomposition of organic mate- 20 km 40 km 60 km rial transfers about 0.2 Gt/year from 80 km 100 km 120 km 140 km Source: NMT, Network for Transport and Environment the biosphere to the geosphere. That is by creation of sediments. Fig. 2: Distance travelled with 1 tonne cargo releasing 1 kg CO2 in the air 6. From the atmosphere to the biosphere About 60-62 Gt/year of carbon is exchanged between the biosphere and the atmosphere. This occurs by photosynthesis and respiration, and pu- Other Transport cost (road) 21.3% trefaction of organic material. There is a net absorption in the biosphere Rail 0.5% International Aviation 1.9% International Shipping 2.7% Domestic Shipping and Fishing Electricity and Heat 0.5% Production 35.0% of about 2.5 Gt/year. However, this could turn, e.g. if the arctic tundra thaws out, which would result in a large volume of CH4 being added to the atmosphere. Fossil-energy-using machinery used for power production both inland and at sea contributes to global carbon emissions and, therefore, the attention has also reached the marine industry, which transports close to 90% of all Manufacturing industry and construction 21.3% Other Energy Industries 4.6% Other 15.3% goods in the world and which is by far the most efficient mode of transporta- Fig. 3: Global carbon emission from various sources tion, see Fig. 2. A relatively small percentage comes About half of the world's transport of The contribution of global carbon emis- from the international shipping, but the goods is transported by MAN B&W low sions from various sources is shown in shipping industry must without a doubt speed engines. Fig. 3. In this picture international ship- contribute and show willingness to re- ping is said to constitute 2.7% of all duce CO2. produced CO2. Total worldwide fuel oil consumption for international shipping is more than 250 million tonnes yearly. 4 How to Influence CO2 COP15 ”Hopenhagen” The Decision-making Copenhagen became the focus of world attention in December 2009. Here, the challenge was for scientists and politicians to agree on a plan to stop global warming caused by the accumulating emissions of CO2 (carbon dioxide) to the atmosphere. Therefore, 20,000 delegates from nearly 200 countries met to discuss and agree on a plan to slow down CO2 emissions in the future. The words of the international chapter on shipping describe shipping as the servant of world trade, which correlates to the fact that the maritime industry is the sixth largest emitter of CO2 emissions. Fig. 4: The Copenhagen Accord The International Maritime Organisation (IMO) warned the COP15 delegates The COP15 was organised under the The Copenhagen Accord that it is difficult to impose disciplines United Nations Framework Convention The Copenhagen Accord, see Fig. 4, on individual vessels, or even some on Climate Change (UNFCCC). is a broad declaration on the climate, countries. which was joined by 188 countries The final draft from COP15 did not in- worldwide. However, the following five Because ships operate across interna- clude a defined emission reduction tar- countries, Sudan, Venezuela, Cuba, tional boundaries, owned in one coun- get for shipping and aviation, despite Nicaragua and Bolivia chose not to join try and registered in another, IMO wants a heavy pressure from the European the declaration. a global approach to be followed. Union (EU). The Copenhagen Accord, the only At present, it is unclear whether a tar- climate change as one of the greatest politically high-level agreement from get will be set by the UNFCCC or by the challenges of our time and, furthermore, COP15, makes no mention of the ship- IMO. A Norwegian proposal, supported that major cuts in global CO2 emissions ping and aviation sectors, so the direc- by the US, Canada, Japan and, poten- are necessary in accordance with sci- tion is not yet decided. tially, Australia, wanted to mention spe- entific recommendations. The objective The Copenhagen Accord recognises cific targets in Copenhagen, instead of is to stop global warming and stabilise As long as the attention is on CO2 calling them ”ambitious” medium, long the increase in global temperature at emissions, increasing average tem- term goals to be set by the IMO, and its below 2 degrees Celsius throughout peratures, ice melting climate changes, aviation equivalent. this century. The declaration does not flooding, hurricanes, etc., there will be mention specific targets for reducing worldwide efforts to introduce emission CO2 emissions, neither medium term, regulations. MAN B&W Diesel How to Influence CO2 5 nor long term. However, the declaration IMO represents 169 member states. As such, the EEDI index describes the lists voluntary CO2 reductions to which Committees and sub-committees con- CO2 emission from a ship while com- a number of countries have committed duct the technical work to update ex- paring it with its benefits, e.g. cargo themselves. isting legislation or development, and transported and distance moved. adopt new regulations. Meetings are The Copenhagen Accord does not de- attended by maritime experts from The baseline for the calculations is from scribe anything concrete regarding the member states, and interested govern- several types of existing ships where shipping industry. However, the text ment and non-government organisa- the ship design, deadweight, passen- does not include anything that stops tions. gers or tonnage are some of the pa- the IMO efforts on cutting CO2 emis- rameters. sions, and the Danish Maritime Author- The regulations in use for the Preven- ity expects that these efforts will con- tion of Air Pollution from ships, IMO Future regulations from IMO will then tinue. The Copenhagen Accord has a MARPOL 73/78: Annex VI and the specify a reduction in the EEDI index broader range than the Kyoto Protocol NOx Technical Code have been in force for new ships based on these baseline in that the big nations USA and China since January 2000. values. can have a positive effect on the nego- However, this regulation does not ad- Below is listed a number of EEDI index tiations in the IMO MEPC (Marine Envi- dress CO2 emissions from ships. reductions scheduled: Therefore, IMO is to undertake the 1.lowering of ship speed The Danish Maritime Authority supports study of CO2 emissions from ships, in 2.use of higher efficiency, e.g. waste the ongoing work of IMO to reduce CO2 cooperation with the UNFCCC, with the emissions by means of globally en- objective of establishing amounts and 3.derating of engines forced IMO regulations. relative percentages of CO2 emissions 4.use of LPG or LNG have also joined the declaration, which ronment Protection Committee). heat recovery from ships as part of the global inven- 5.optimisation of the hull The International Maritime Organisation (IMO) tory. The study should estimate emis- 6.optimisation of the propeller sions for the most recent years and 7.coating. IMO is the specialised agency under address how shipboard emissions and the United Nations that prepares the their relative percentage contribution to Status of the EEDI: The community is applicable regulations for the marine global CO2 levels can be changed in asked to evaluate the EEDI formulas for industry. The organisation sets interna- the future. different types and sizes of vessels. The tional standards for the shipping indus- basic construction of the formula and try that can be accepted and adopted The status for this work is that a design the baselines are now fixed, but indi- by all its members. index and an operational indicator have vidual coefficients are still evaluated. been developed as tools for quantifying IMO’s main task is to develop and and optimising of design and operation The second tool is the operational in- maintain a comprehensive and regula- for reduction of CO2 emissions. dex, also referred to as the Energy Ef- tory framework for the shipping indus- ficiency Operational Indicator (EEOI) – a try, and its remit today includes safety The purpose of the design index, also tool to evaluate the operational behav- and environmental areas, legal matters, called the Energy Efficiency Design In- iour of efficiency onboard. technical cooperation, maritime secu- dex (EEDI) is first of all to reduce green- rity, and the efficiency of shipping. house gasses (CO2) emitted from ships, but also to stimulate the development of energy-efficient ships. 6 How to Influence CO2 Choice of Engine Power and rpm Major Propeller and Main Engine The layout of the propeller and the en- Parameters measurement of the energy efficien- gine is essential for the highest possi- The efficiency of a two-stroke main en- cy during each voyage ble efficiency of the main engine and, gine particularly depends on the ratio of evaluation of the operational per- thereby, the efficiency of ship propul- the maximum (firing) pressure and the formance by owners or operators sion. mean effective pressure. The higher the The objective of the EEOI is: continued monitoring of individual ratio, the higher the engine efficiency, ships The derating of the engine, the increase i.e. the lower the Specific Fuel Oil Con- evaluation of any changes made to of the propeller diameter and use of sumption (SFOC). the ship or its operation. electronically controlled engines are described in this chapter. In principle, the coverage of EEOI Furthermore, the larger the stroke/bore ratio of a two-stroke engine, the higher should include all new and existing In general, the larger the propeller di- the engine efficiency. This means, for ships engaged in transportation. ameter, the higher the propeller efficien- example, that a long-stroke engine type, cy and the lower the optimum propeller e.g. an S80ME-C9, will have a higher The status of EEOI is that it has been speed referring to an optimum ratio of efficiency compared with a short-stroke implemented on a trial basis since the propeller pitch and propeller diam- engine type, e.g. a K80ME-C9. 2005. eter. For the moment, it is being used on a When increasing the propeller pitch programme layout have therefore in- voluntary basis by some owners and for a given propeller diameter, the cor- cluded an investigation of whether an operators to collect information on the responding propeller speed may be even larger stroke/bore ratio than for outcome and experience in applying reduced and the efficiency will also be the S-type engines would be demand- the EEOI. slightly reduced, but of course depend- ed by the market, when considering the The latest considerations on engine ing on the degree of the changed pitch. possible and most optimal future ship IMO objectives: The same is valid for a reduced pitch, hull designs. This investigation is cur- 1.that UNFCCC parties continue en- but here the propeller speed may in- rently ongoing. trusting IMO with the regulation of crease. greenhouse gas emissions from international shipping, and 2.that the subsequent IMO regulatory regime is applied to all ships, regardless of the flag they fly. IMO represents all countries – this is the opinion of the industialised countries. MAN B&W Diesel How to Influence CO2 7 Compared with a camshaft (mechanically) controlled engine, an electronically controlled engine has more parameters that can be adjusted during the Fuel consumption per day t/24h 50 pared with the MC/MC-C engine types, When the design ship speed is reduced, the corresponding propulsion M2 M3 M4 Alt. 2: 6S60MCC8 derated SMCR=11,900 kW at 105 r/min 45 Alt. 3: 6S60MCC8 derated SMCR=11,680 kW at 98.7 r/min have a relatively higher engine efficiency under low-NOx IMO Tier II operation. M1 Alt. 1: 5S60MCC8 nominal (Basis) SMCR=11,900 kW at 105 r/min engine operation in service. This means that the ME/ME-C engine types, com- Reduced fuel consumption by derating IMO Tier ll compliance Alt. 4: 6S60MEC8 derated SMCR=11,680 kW at 98.7 r/min 40 Reduction () of fuel consumption: 35 power and propeller speed will also be reduced, which again may have an in- 30 fluence on the above-described propeller and main engine parameters. Average service load 80% SMCR 25 65 70 75 80 Total Total Propeller t/24h % % Engine % 0.00 0.0 0.0 0.0 1.14 2.9 0.0 2.9 1.60 4.1 1.8 2.3 2.39 6.1 1.8 4.3 85 90 95 The following is a summary of the major 100 %SMCR Engine shaft power parameters described, see also Figs. 5 and 6. Fig. 5: Relative fuel consumption in normal service of different derated main engines for a 75,000-dwt Panamax product tanker operating at 15.1 knots Propeller Larger propeller diameter involving: Higher propeller efficiency Lower optimum propeller speed (rpm) Lower number of propeller blades in- Fuel consumption per day IMO Tier ll compliance Fuel consumption per day kg/24h/teu t/24h 300 10K98ME7 SMCR=60,000kW × 97.0 r/min 35 30 Slightly higher propeller efficiency Increased optimum propeller speed 25 9S90MEC8 SMCR=43,100 kW × 78.0 r/min 150 load vice ser ine R E ng MC S 90% R SMC 80% R M S C 70% % Reference 25.0 kn 23.0 kn 23.0 23.5 24.00 24.5 80 Fuel reduction () per day: 15 22.5 100 90 26.0 kn Ship speed Propeller 100 130 110 20 (rpm) (from 6 to 5 blades means approximately 10% higher rpm) 200 Relative fuel consumption per day % 120 250 volving: 12K98MEC7 SMCR=69,800kW × 102.1 r/min 25.0 37.4% 1.3% Engine 2.3% Total: 41.0% 25.5 70 60 50 26.0 26.5 kn Design ship speed Main engine Increased pmax/pmep pressure ratio involving: Higher engine efficiency (e.g. by derating) 8 How to Influence CO2 Fig. 6: Relative fuel consumption per day of different main engines for different design ship speeds of an 8,000-teu Post-Panamax container vessel Larger stroke/bore ratio involving: Higher engine efficiency (e.g. S-type Case 1: 75,000 dwt Panamax Product Derated 9S90ME-C8 versus 10K98ME7 Tanker at 15.1 knots ship speed and 12K98ME-C7 engines have higher efficiency compared with K-type engines) Nominally rated 5S60MC-C8 versus derated 6S60MC-C8 and 6S60ME-C8 Influence of reduced ship speed Influence of increased propeller diameter. Use of electronically controlled engine Influence of derating of engine instead of camshaft controlled: Influence of derating and increased Engine Efficiency propeller diameter The relationship between engine effi- Influence of using electronically con- ciency and CO2 in the exhaust gas is trolled engine directly linked. When the carbon in the Higher engine efficiency (improved control of NOx emissions). fuel is burned, the C and O2 will form Case 2: 8,000 teu Post-Panamax Con- the CO2 and, therefore, the CO2 emis- tainer Vessel at reduced ship speed sion ratio is primarily determined by fuel consumption and the fuel composition, the latter being rather constant for fossil fuels: CO2 approx. 3,200 g/kg of fuel, % Thermal efficiencies 60 Low-speed diesel 50 Medium-speed diesel based on 86% carbon in fuels. 40 Combined cycle gas turbine and plant efficiency, the lower the CO2 30 Steam turbine level. 20 Gas turbine This means that the higher the engine If we look at different types of prime 10 movers, see Fig. 7, it is obvious that the Load 0 50 modern diesel engine is the most effi- 100 % cient machinery used as prime mover today. Fig. 7: Different prime mover types If we then look into the development of the engine since 1950, Fig. 8 shows a SFOC g/kWh 2007 huge development of the engine effi- 250 ciency, bringing it close to the so-called Carnot efficiency. 200 SFOC Full-rated De-rated Ideal Carnot cycle 150 NOx g/kWh NOx 100 20 K98FF 84VT2BF180 0 1940 1960 GB/GBE GFCA MC/MC-C KGF 1980 ME/ME-C/ME-B 2000 2020 ed into mechanical work in an engine cycle, it can be shown that the maximum efficiency possible is obtained if the cycle is reversible (that the process 10 50 Because the thermal energy is convert- can come back to where it started). And further that only a reversible proc- 3.4 Year Fig. 8: Engine efficiency development MAN B&W Diesel How to Influence CO2 9 ess has the same maximum efficiency. ficiency can be raised to 57% and 58%, WHR systems has so far been depend- A well-known and much used example respectively. Corresponding to 14% ing on the cost of HFO, the expecta- of such a cycle is the Carnot process. and 18% of engine efficiency. tions to the development in the cost of HFO and, furthermore, the willingness Calculations and measurements have A number of ships, though limited, have of the shipyards to deliver ships de- shown that we are close to the high- been built with such systems over the signed and built for the WHR concept. est efficiency possible, according to past 25 years. Shipowners’ interest in the Carnot process, with the standard engine design available today, without extra equipment. Exh. Gas boiler This also means that if we want to in- Saturated steam for heating purposes crease the engine efficiency and, there- Emergency generator TG: Turbogenerator PT: Power turbine TC: Turbocharger Switchboard Superheated steam Generator by, reduce the CO2 content, we need to TG PT Diesel generators look for other methods and techniques used in connection with the application of diesel engines. TC Shaft/motor generator Exhaust gas receiver Main engine Waste Heat Recovery System The most efficient way to increase the total efficiency of a ship with a twostroke engine is to utilise the waste heat of the engine. Fig. 9: Thermo efficiency system Waste heat is collected primarily from the heat energy of the engine exhaust gas. Technology with power turbines, Generator i.e. steam turbines in combination with high-efficiency turbochargers and boilers, has already shown system ef- Steam turbine ficiencies of 55%. This corresponds to a 10% increase in efficiency and 10% lower fuel consumption and CO2 emission. The highest theoretical efficiency is close to 60%. If waste heat recovery is combined with NOx reduction methods and SAM (scavenging air moisturisation) or EGR (exhaust gas recirculation), the total efFig. 10: Waste heat recovery 10 How to Influence CO2 Power turbine Experience has shown that the reli- SFOC g/kWh ability of the system can be high, but 183 182 181 180 179 178 177 176 175 174 173 172 171 170 169 168 167 166 165 164 installation is complicated, and space for extra equipment is required, and the equipment requires maintenance. These are all important factors that the operators take into account when ordering a new ship. If we make a parallel to the two-stroke power stations, a number of plants have either steam turbines, power turbines or both, but the power station industry calculates with longer payback 0 10 20 30 40 50 60 70 80 The question is what effect the future regulation of CO2 will have on the adoption rate of the WHR system in the marine industry. 100 110 Engine load % times for the equipment, and has unlimited space, see Figs. 9 and 10. 90 10K98ME7-TII with 3 x TCA88-21 SMCR: 57,200 kW at 97.0 RPM Opt. point: 100.0 % IMO NOx Tier II comp. +Exhaust Gas By-pass 10K98ME6-TII with 3 x TCA88-21 SMCR: 57,200 kW at 94.0 RPM Opt. point: 100.0 % IMO NOx Tier II comp. 10K98ME7-TII with 3 x TCA88-21 SMCR: 57,200 kW at 97.0 RPM Opt. point: 100.0 % IMO NOx Tier II comp. Turbocharging Layout The well-known influence on engine Fig. 11: Low-load layout with exhaust gas bypass efficiency from the turbocharger also makes the design, layout and application of turbochargers essential. SFOC g/kWh With the following four technologies, 180.0 potential for increases in energy effi- 178.0 ciency at reduced load exists. All four 176.0 technologies are proven and available: 174.0 172.0 Exhaust gas bypass (EGB) Variable turbine area Turbocharger cut-out Sequential turbocharging, see Figs. 11 and 12 Turbocharger cut-out can also be 170.0 168.0 166.0 164.0 162.0 25 35 Basis 45 55 VTA 65 75 TC cut 1/3 85 95 EGB ME2 105 Load % made for engines with two and four turbochargers. Fig. 12: Turbocharger layout or charge air tuning MAN B&W Diesel How to Influence CO2 11 LNG and LPG as Fuel The electronically controlled ME-GI high-pressure gas injection engine was introduced some years ago, primarily to the LNG market. The ME-GI engine is designed to burn the boil-off gas evaporating from the liquefied gas in the LNG storage tanks onboard. Today, we Main Engine ME-GI see much wider application potential for the ME-GI engine. LNG fuel supply system Existing and future expanded emission control areas (ECA) call for the use of low-sulphur fuels within 200 nautical miles from the coast. And with the current low price of LNG combined with the operational flexibility of the MEGI engine, it is our expectation that a broad range of vessels in the merchant Containment systems for LNG fleet will be ordered with an ME-GI propulsion plant in the future. • IHI type B tanks low pressure tanks, BOR 0.2 %/day • TGE type C tanks 4-9 barg pressure (up till 50 travelling days) BOR 0.21 - 0.23 %/day The emission control areas need to be introduced through IMO. Fig. 13: Gas as fuel on board container vessels Fig. 13 illustrates a container vessel. Operation on gas, not only reduces SOx and NOx emissions significantly, but where we are testing further develop- pumping liquid gas through an evapora- also CO2. Both LPG and LNG are low- ment and optimisation of the ME-GI tor to the engine, and gas compressors carbon emitting hydrocarbon fuels, and technology towards high efficiency, compressing NG to the engine at the the resulting CO2 emission per kWh is high reliability or reduced emission. pressure needed. These systems have approx. 20% lower than for HFO, and gained successful experience with re- approx. 30% lower than for coal, see Also targets as lower pilot oil amount Table 1. and lower minimum load for gas operation is considered in the optimisation. As a result of the increased global inter- gard to safety, reliability and availability. During the demonstration and performance optimisation on our research est for the ME-GI engine, we will at the The gas supply system is an essential engine, DSME will supply and dem- beginning of 2011 demonstrate our test component for gas operation. Thor- onstrate their cryogenic liquid natural engine in Copenhagen as a 4T50ME-GI ough investigations in cooperation with gas pump, evaporator and gas supply engine. suppliers, classification societies, yards control. Fig. 13 illustrates the unit that and engine builders have therefore will be delivered by end-2010 to be in- As part of the development plan, we been ongoing for a number of years. stalled at the MAN Diesel & Turbo re- have also developed an ME-GI test rig, Today, we can show cryogenic pumps search facilities in Copenhagen. 12 How to Influence CO2 Emission comparison S50ME-C8-GI engine compared with the equivalent ME or MC type engine 48% propane and 48% butane and 5% pilot oil compared with HFO operation (3.5% sulphur) Load SFOC Pilot oil Gas % g/kWh % % CO2 ME/MC g/kWh 100% 170 5 95 559 472 12 0.60 13.5 11.9 75% 166 7 93 546 461 12 0.78 14.7 12.9 50% 179 10 90 557 470 12 1.19 14.5 12.7 14.4 12.9 ME-C8-GI g/kWh SOx ME/MC g/kWh ME-C8-GI g/kWh IMO NOx cycle: NOx Tier II ME/MC ME-C8-GI g/kWh g/kWh NOx from fuelbound nitrogen not included in estimated NO x values Actual emissions may deviate due to actual optimisation of engine Table 1: Comparison of emissions from an HFO burning and a gas burning S50ME-GI type of engine A demonstration will be arranged of the 4T50ME-GI in 2011 for class societies, 3) Test on R&D engine 4) First production engine Verification test and TAT customers and licensees of MAN B&W low speed two-stroke engines, see Fig. 14. Diesel Engines Burning Biological Oils and Fat The motivation to consider biofuels and fat as fuel is based on the objective to reduce greenhouse gas (CO2) emissions and use renewable and green energy sources instead of depleting the limited fossil fuel available. Today, biofuel and fat are used on a number of medium and low speed power plants worldwide. The combustion of biofuel instead of mineral fuel results in a net-reduction 2) Test on rig 1) Design and Calculation of greenhouse gas emissions and other combustion-related pollutants, while at Fig. 14: ME-GI development plan the same time allowing for appropriate disposal of the waste biological oils of residential, commercial and industrial origin. MAN B&W Diesel How to Influence CO2 13 The design and construction of medi- and gas, and an alternative to the use The MAN Diesel & Turbo reference lists um and low speed diesel engines from of high-priced distillate fuels in IMO and include seven MAN B&W two-stroke MAN Diesel & Turbo allows them to op- locally designated emission control ar- low speed engines – some still under erate on some low-quality liquid fuels eas (ECA). construction – and more than 30 MAN such as crude vegetable oils and some four-stroke medium speed engine waste and recycled biofuel, which is A number of tests involving use of liquid plants sold for operation on biological also considered the cheapest biofuel biofuel and fat have been performed oils and fat. Most of the engines on the available. since the mid-1990s. Tests of rapeseed reference lists have logged thousands oil, palm oil, fish oil, frying fat and fat of hours in operation on, respectively, The possibility of combining sound eco- from slaughterhouses have been per- cooking oil, palm oil, soy rapeseed and nomics with superior eco-friendliness formed on three different occasions at castor beans, see Fig. 16. in the operation of a prime mover has MAN Diesel & Turbo. led MAN Diesel & Turbo to initiate the The conclusion from using biofuels and development and optimisation of liquid Today, a number of medium and low fat is the following: biofuel combustion on low speed MAN speed plants are in operation in Eu- B&W diesel engines. rope, all with good service experience. Today, biological oil and fat is used on For comparison, Table 2 shows the fuel some power stations where logistics spec. of different biofuels and the HFO makes it convenient, and often the specification. As can be seen the bio- price of the biofuel is set politically. fuels and distillates are close in com- the use matches the minimum MAN Diesel & Turbo fuel specification no important deviation in diesel combustion process and heat release no important deviation in fuel injection pattern parison. HFO in the marine market today is ap- The most common biofuels are illus- no change in engine efficiency prox. 250 million tonnes per year. It is trated in Fig. 15. redesign of fuel injection equipment The expected world consumption of no important deviation in engine performance not expected that the biofuel will ever allows 5 and 15 TAN, respectively. fully replace mineral and fossil fuels, but it could be a supplement to HFO Vegetable oil treated, Bio Diesel EN 14214 non transesterified Marine diesel ISO 8217 Heavy Fuel Oil ISO DMB 8217 RM Density/15 °C 920 - 960 kg/m³ 860 - 900 kg/m³ < 900 kg/m³ 975 - 1010 kg/m³ Viscosity at 40 °C/ 50 °C 30 - 40 cSt 3.5 – 5 cSt < 11 cSt < 700 cSt /50 °C Flashpoint > 60 °C > 120 °C > 60 °C > 60 °C Cetane no. > 40 > 51 > 35 > 20 Ash content < 0.01 % < 0.01 % < 0.01 % < 0.2 % Water content < 500 ppm < 500 ppm < 300 ppm < 5 000 ppm Acid no. (TAN) <4 < 0.5 - - Sulphur content < 10 ppm < 10 ppm < 20 000 ppm < 50 000 ppm Calorific value approx. 37 MJ/kg approx. 37.5 MJ/kg approx. 42 MJ/kg approx. 40 MJ/kg Table 2: Comparison of fuel characteristics 14 How to Influence CO2 A common practise that is expected in the industry if distillates become the dominant fuel in ECA areas is that even more biofuels will be blended in the distillates used for marine application. Castor Bean Soy Consists of 40 – 50% usable Oil Palm Oil Rape Seed According to the ISO 8217 marine fuel standard, it is not acceptable to blend biofuels or any other non-fossil fuel product into the fuel oil. However, this already occurs today, and the biofuel is typically added for political or economical reasons, and it is expected that ISO 8217 will need to include this in coming standards. There are thorough considerations to be made when biofuel is mixed into marine fuels. Compatibility issues concern whether the fuel is mixable and the possibility for introducing biological bacteria. Fig. 15: Sources of biofuels Fig. 16: The 7L35MC-S plant at Brake MAN B&W Diesel How to Influence CO2 15 Green Ship of the Future Many fields of knowledge are involved, Carbon War Room A group of maritime companies, A. P. such as systems for recycling of heat The organisation called the Carbon War Møller-Mærsk, MAN Diesel & Turbo and energy, optimisation of the hull, propel- Room is an NGO organisation that was Odense Steel Shipyard, have set up a lers and rudders as well as optimisation launched by, among others, the CEO task force to develop and demonstrate of the draft and speed for a given route and founder of Virgin Air, Richard Bran- green technologies within shipping and and arrival time, and fouling of the hull son. shipbuilding. and propeller. MAN Diesel & Turbo’s first contact with The goal of the Green Ship of the Fu- MAN Diesel & Turbo contributes with the organisation was at a reception at A. ture is to develop strategies to reduce technologies such as EGR (exhaust gas P. Møller-Mærsk (APM) in Copenhagen CO2 by 30%, SOx by 90%, NOx by 90% recirculation), water in fuel (WIF), waste in connection with the COP15 meeting. and particulate emissions, both from heat recovery system, autotuning and On that occasion, Richard Branson, ships in service and from newbuildings, general genset and engine optimisa- José Maria Figueres (former president see Fig. 17. tion. Furthermore, MAN Diesel & Turbo of Costa Rica) and Niels Smedegaard also cooperates with Aalborg Industries Andersen, CEO of APM, spoke of how on the testing of a full flow scrubber. the efforts to cut CO2 emissions may All Danish companies and organisations that are able to demonstrate a go hand in hand with new business op- technology with potential for reduction The Danish Shipowners Association portunities if traditional barriers in the of emissions from machinery, propul- believes that the merchant fleet will be shipping industry are removed. sion, operation and logistics are wel- able to increase its efficiency by at least come to join. 15% by 2020. If the Carbon War Room can initiate and contribute to new solutions and NOx/SOx reduction systems EGR system installed 50% NOx reduction CO2 / Fuel consumption reduction systems WHR system installed 12% CO2/ fuel reduction SAM & WIF 60% NOx reduction up to 20% when combined with SAM/WIF SCR and Exhaust gas scrubber Pump & auxiliary system optimisation 90% NOx reduction 1% CO2/ fuel reduction 90% SOx reduction Dual/Multi MCR ratings 3% CO2/ fuel reduction Open cooperation Demonstration projects identified for Climate summit in Copenhagen 2009 Fig. 17: The green ship of the future – 2012 16 How to Influence CO2 Automated Engine Control 1% CO2 / fuel reduction The air could be produced by the high- the introduction and effect of the CO2 Conclusion and Other Measures Discussed to Increase Efficiency reduction method. Methods that can Many technologies are available in the gine or by a separate air compressor. be both practical and applicable with- market to, in some way, reduce CO2 out spoiling the safety and reliability re- emissions from the use of fossil fuels. In principle, wind can provide propul- quired in the people and goods trans- Some things are outside the influence sion energy to supplement conven- portation sector. of MAN Diesel & Turbo and our licen- tional fuel. The German company Sky sees, and are more controlled by the Sail is probably the most advanced of The Carbon War Room organisation shipowners and requirements from the a number of companies looking, once has just been created, and it is ex- authorities. again, to harness the wind for ship change ways of application, it will ease pected that many more people and or- efficient turbocharger on the main en- power. Its kite-based wind assistance ganisations will be involved in the near One method is the air friction technolo- system has been tested on several future. gy, which reduces the friction between installations and has achieved most the steel hull bottom and the water by encouraging results with most of the introducing a layer of air between the recent developments concentrating on hull and the water. The air will be lo- the computerised control and launch- cated in a narrow hollow in the specially ing system, integrating the deck com- designed hull bottom. ponents into one single unit. The kite-based wind assistance is not suitable for all ship types and routes. Large container ship Propulsion power needed 25 knots refers to 100% relative propulsion power A reduction of 5 knots will result in 38% propulsion power requirement, or 48% fuel consumption per journey. But there might be a fuel saving and CO2 reduction potential for vessels regularly travelling routes with a favourable profile of prevailing winds. The engine speed has a huge impact on the use of power and, thereby, also CO2 emissions. If the authorities wish to restrict the acceptable level of speed for the different types of merchant ships, it will influence the size of engines, but expectedly also increase the number of ships needed in the world. In Fig. 18, we have shown two examples of the ship speed’s influence on the power needed. When comparing the scrubbing of HFO Reduced fuel oil consumption Reduced exhaust emissions Optimised cargo capacity in fleet and the use of distillates even the refinery process is investigated. As such, Fig. 19 shows data received from Aalborg Industries of the CO2 used for Fig. 18: Power vs. ship speed MAN B&W Diesel How to Influence CO2 17 Scrubbing (SW) Fuel: Fuel consumption [kg/MWh] Fuel LHV [kJ/kg] Carbon content [kg CO2/kg fuel] Sulfur content [% S (w/w)] 180 40,500 3.16 2.7 182 40,500 3.16 2.7 171 42,619 3.15 0.1 kg CO2/MWh: Generated by the engine Released from sea water Desulphurisation of heavy fuel oil 570 9 0 574 13 0 540 0 68 Total - Reference Additional CO2 [%] 579 579 0 588 579 1.4 609 579 5.1 the CO2 used for HFO scrubbing operation. This means that the use of distillates and limits, or avoid HFO in 2020, might not be the right solution when considering the overall CO2 emissions. Singapore-based Ecospec claims to be able to remove 77% of CO2, 66% of NOx, and 99% of SOx by means of exhaust gas aftertreatment. Results that could give a huge contribution to exhaust gas emission reduction. So far, MAN Diesel & Turbo has discussed the technique used with Ecospec to understand the chemical reaction and energy amount used, but we still need to see the process working as promised, fulfilling the emission reductions. Another technique investigated from Distillate No abatement production of distillate, compared with Assumptions: Engine fuel efficiency 49.3 % Additional fuel consumption due to scrubber 0.75 % Additional CO2 due to desulphurisation of HFO 12 % SO2 disposed at land 30 % S to CO2 conversion factor in sea water 2 mol CO2 /mol SO2 (worst case) Fig. 19: CO2 used for production of distillate many parts of the industry is CO2 storage. This concept is based on carbon Technically, CO2 is double the density capture and storage (CCS). of liquefied petroleum gas, and will be for the environment and still practical for able to carry double the amount of CO2 marine applications. Carbon captured mainly from land- compared with LPG. based power stations, gas processing As a member and advisor, MAN Diesel & and oil refineries and stored in the un- The point is that there are many spe- Turbo participates in the debate in Euro- derground storage is still only a blue- cialists with different views on the influ- mot, IMO, CIMAC, EPA, CARB, etc., to print. Ultimately, it will be politics and ence of CO2 and the trade-off for other provide our expertise and influence the economy that determine when CCS emissions. decisions to be made so that optimal so- can be realised, and when it does, a lutions are found. huge potential for CO2 transporting The final decision is taken by politi- ships is expected, giving a new market cians, but in the end it is important that By this paper, we hope to have enlight- potential for engines and ships. MAN Diesel & Turbo and our licensees ened you on MAN Diesel & Turbo’s tech- Maersk Tankers estimate a potential influence the decisions that are made nical considerations and expectations to demand for 380 ships in the North Sea and support the most optimal solutions the possibilities of influencing the emis- alone. 18 How to Influence CO2 sion of CO2. All data provided in this document is non-binding. This data serves informational purposes only and is especially not guaranteed in any way. Depending on the subsequent specific individual projects, the relevant data may be subject to changes and will be assessed and determined individually for each project. This will depend on the particular characteristics of each individual project, especially specific site and operational conditions · Copyright © MAN Diesel & Turbo · Subject to modification in the interest of technical progress. · 5510-0083-00ppr Jul 2010 · Printed in Denmark MAN Diesel & Turbo Teglholmsgade 41, 2450 Copenhagen SV Denmark Phone+45 33 85 11 00 Fax +45 33 85 10 30 [email protected] www.mandieselturbo.com
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